A measurement system includes: a first voltage measurement unit, which measures a first voltage as a line voltage between first and second phases of a three-phase power line configured by three phases including the first, second, and a third phase; a first current measurement unit, which measures a first current as a current of the first phase; a third current measurement unit, which measures a third current as a current of the third phase; a determination unit, which determines a direction of rotation of the three phases based on the first voltage and the first current; and a computation unit which, based on at least the determination of the direction of rotation by the determination unit, computes a change in a current phase due to a load device in each of the first, third, and a second current as a current of the second phase.

A method for identifying consumer phase connectivity in low-voltage distribution network based on voltage association characteristics is provided. The specific steps thereof are: first, acquiring users to be identified and voltage time series data of three-phase buses on the low-voltage side of the low-voltage distribution network where the users to be identified are located; then, calculating voltage time series curve correlation coefficients among the users, and classifying a user having the maximum voltage time series curve correlation value with respect to the user into one category to form a user category set; then, based on the user classification, determining an initial consumer phase connectivity according to voltage association characteristics between the users and the three-phase buses on the low-voltage side of the low-voltage distribution network; finally, verifying the initial consumer phase connectivity according to the voltage association characteristics among the users to obtain a final consumer phase connectivity identification result.

A method for identifying consumer phase connectivity in low-voltage distribution network based on voltage association characteristics is provided. The specific steps thereof are: first, acquiring users to be identified and voltage time series data of three-phase buses on the low-voltage side of the low-voltage distribution network where the users to be identified are located; then, calculating voltage time series curve correlation coefficients among the users, and classifying a user having the maximum voltage time series curve correlation value with respect to the user into one category to form a user category set; then, based on the user classification, determining an initial consumer phase connectivity according to voltage association characteristics between the users and the three-phase buses on the low-voltage side of the low-voltage distribution network; finally, verifying the initial consumer phase connectivity according to the voltage association characteristics among the users to obtain a final consumer phase connectivity identification result.

Methods, systems, and apparatus, including computer programs stored on a computer-readable storage medium, for obtaining a reference phase signal that is synchronized with an alternating current (AC) phase of a multi-phase electrical power distribution system. The apparatus obtains output signals from sensors, each output signal representative of an electromagnetic emission detected by a respective sensor. The apparatus identifies, based on comparing respective phases of the output signals to the reference phase signal, a particular AC phase of the multi-phase electrical power distribution system associated with a source of the emissions. The apparatus provides an indication of the particular AC phase to a user.

Methods, systems, and apparatus, including computer programs stored on a computer-readable storage medium, for obtaining a reference phase signal that is synchronized with an alternating current (AC) phase of a multi-phase electrical power distribution system. The apparatus obtains output signals from sensors, each output signal representative of an electromagnetic emission detected by a respective sensor. The apparatus identifies, based on comparing respective phases of the output signals to the reference phase signal, a particular AC phase of the multi-phase electrical power distribution system associated with a source of the emissions. The apparatus provides an indication of the particular AC phase to a user.

Methods, systems, and apparatus, including computer programs encoded on a storage device, for identifying phases of electrical grid wires are disclosed. A method includes identifying, within an image of a utility pole, a cross-arm supporting multiple wires; identifying a cardinal orientation of the cross-arm based on characteristics of the image; and determining, based on the cardinal orientation of the cross-arm, an electrical phase for each of the wires supported by the cross-arm. Identifying the cardinal orientation of the cross-arm includes: determining an orientation of the cross-arm relative to an axis of a field of view of the image; determining a cardinal orientation of the axis of the field of view; and estimating the cardinal orientation of the cross-arm based on an angular difference between the orientation of the cross-arm relative to the axis of a field of view and the cardinal orientation of the axis of the field of view.

Methods, systems, and apparatus, including computer programs encoded on a storage device, for identifying phases of electrical grid wires are disclosed. A method includes identifying, within an image of a utility pole, a cross-arm supporting multiple wires; identifying a cardinal orientation of the cross-arm based on characteristics of the image; and determining, based on the cardinal orientation of the cross-arm, an electrical phase for each of the wires supported by the cross-arm. Identifying the cardinal orientation of the cross-arm includes: determining an orientation of the cross-arm relative to an axis of a field of view of the image; determining a cardinal orientation of the axis of the field of view; and estimating the cardinal orientation of the cross-arm based on an angular difference between the orientation of the cross-arm relative to the axis of a field of view and the cardinal orientation of the axis of the field of view.

A method, apparatus, and system for identifying electrical phases connected to electricity meters are disclosed. Voltage time series data of electricity meters are collected over a preselected collection time period, and three initial kernels representing three line-to-neutral phases are generated based on voltage correlations of meter-to-meter combinations. Three new kernels are then generated based on correlation values calculated for each of the three initial kernels with each electricity meter, and electricity meters are clustered into three groups based on average correlation values associated with each electricity meter. Six new kernels representing six phases are then formed based on the average correlation value associated with each electricity meter, and a predicted phase is assigned to each electricity meter based on correlation values of the electricity meter with each of the six new kernels based on the voltage time series data.

A method, apparatus, and system for identifying electrical phases connected to electricity meters are disclosed. Voltage time series data of electricity meters are collected over a preselected collection time period, and three initial kernels representing three line-to-neutral phases are generated based on voltage correlations of meter-to-meter combinations. Three new kernels are then generated based on correlation values calculated for each of the three initial kernels with each electricity meter, and electricity meters are clustered into three groups based on average correlation values associated with each electricity meter. Six new kernels representing six phases are then formed based on the average correlation value associated with each electricity meter, and a predicted phase is assigned to each electricity meter based on correlation values of the electricity meter with each of the six new kernels based on the voltage time series data.

An example welding-type power supply includes: power conversion circuitry configured to convert three-phase input power to welding-type power; a reference node coupled to each winding of the three-phase input power via a corresponding impedance; and a phase detection circuit coupled to the reference node and configured to determine a number of phases connected to the input based on comparing a frequency of a signal at the reference node to a threshold frequency.